Apparatus for the production of controlled saturated steam vapor



July 5, 1955 L 2,712,471

APPARATUS FOR THE PRODUCTION OF CONTROLLED SATURATED STEAM VAPOR Filed June 24, 1952 N gfl' N 0' C L g I "I I I I I I7 I I I L I INVENTOR.

GEORGE LEO HALL BY It ATTORNEY United States Patent 0 APPARATUS FOR THE PRODUCTION OF CON TROLLED SATURATED STEAM VAPOR George Leo Hall, Atlanta, Ga. Application June 24, 1952, Serial No. 295,315

4 Claims. (Cl. 29984) The present invention relates broadly to apparatus for the production of selected mixtures of steam and detergent chemicals, and more particularly to such apparatus to be used in various applications, such as steam cleaning, degreasing, spraying of chemicals, etc.

This application is a continuation-in-part of my copending application, Serial No. 160,186, filed May 5, 1950, now Patent No. 2,638,383 entitled Apparatus for the Production of Controlled Saturated Steam Vapor.

One of the main disadvantages of somewhat similarly constructed devices is that when the desired chemicals, which are usually in powdered form, are mixed with cold water into a solution, the chemicals are merely held in suspension in the water temporarily and when left standing fora short time, a considerable percentage of such chemicals will separate from the water and be deposited, in the form of crystals, in certain parts of the mechanism, thus causing considerable loss in the efficiency of the mechanism and the resulting increase in expense to the owner of the machine. It is a well known fact that such chemicals dissolve more readily and are held in suspension longer in hot water than in cold.

Another disadvantage of such machines as above mentioned is that no provision has been made to automatically agitate the chemical solution and to keep the solution tank hot while the machine is operating, in order that only thoroughly mixed chemical solution, in a preheated condition, flows through the solution lines, check valves, and pumping units of the machine.

Still another disadvantage of other similar machines is the fact that both water and chemical solutions are introduced into the pumping units and heating coils cold, resulting not only in the disintegration on the chemical solution, but in sub-zero weather such liquids freeze before reaching the pumping units; and, as a consequence,

such machines cannot be used except in enclosed areas where the temperature is above 30 or 32 degrees Fahrenheit, since even if such machines should be started up in a Warm enclosure, no provision has been made to keep the water and chemical solutions from freezing if the unit is taken outside to be operated during sub-zero weather.

Another disadvantage to the above mentioned machines is that after being in operation for a relatively short time the coils and other heating elements become encased in soot and other waste products of the fuel used for heating causing a definite decrease in the efliciency and proportionate increase in operating cost to the owner of the machine.

One object of my present invention is to provide apparatus for producing steam, steam vapor, or hot water, and wherein any desired chemical may be introduced in any proportion into the steam or hot water line.

Another object of the invention is to provide steam generating apparatus that will operate in sub-zero weather and wherein any desired chemicals may be introduced in any proportion directly into the hot water line, in a preheated state.

A further object of the invention is to provide means Patented July 5', "i355 whereby hot water generated in the heating vat may be used to agitate the chemical, by convective currents, in the solution tank or other container and to maintain same in a heated condition in order that no chemical solution flows through the solution feed lines, check valves or pumping units, in a cold state.

A still further object of the invention is to provide means for regulating the amount of chemical solution to be fed into the steam generating line as above mentioned, said means to be capable of completely shutting off the supply of chemical solution to permit the flushing of an object with clear hot water or steam vapor.

Still another object of the invention is to provide means for the inhibition of the formation of soot and other waste products of the fuel on the coils and other heating elements.

Another object of my present invention is to provide a multiplicity of pumping units, one, or more, of which may be so connected to draw from sources other than the regular float tank supply and to pump directly into the steam outlet of the heating coil to permit the spraying of insecticides, water-base paints, etc. without such chemicals being pumped through the heating coils; or to bypass the heating coils with a portion of the water supply from the float tank and pumping same direct into the steam outlet, to which the flexible steam hose is attached, for the purpose of saturating the steam being discharged from the heating coils at that point in order to prevent damage to the flexible hose from dry steam.

Still another object is the locating of the water supply float tank, which contains hot water, under the combustion chamber in such manner as to permit hot water vapors to float up into the combustion chamber, resulting in the inhibition of the collection of soot and other waste products of the fuel on the coils and other heating elements.

Another object is to provide means for the floating of hot water vapors into the combustion chamber for the purpose of introducing a type of oxyhydrogen flame under the heating coils, resulting in a quicker and more eflicient heat and lower fuel costs.

From the foregoing, it will be seen that my present invention can be used for such operations as the cleaning of the exteriors of buildings, road building equipment, and other types of work which must be performed in an open area regardless of the prevailing weather.

Other objects and advantages will be apparent in the course of the following detailed description when viewed together with the accompanying drawings in which like characters of reference designate corresponding parts throughout, and wherein:

Fig. 1 is a diagrammatical view of an embodiment of the invention.

Fig. 2 is a wiring diagram of the electrical circuit of the invention.

In Fig. 1, numeral 10 designates a water heating vat provided with inner and outer side walls 11 and 12 which define a reservoir area 13. Placed adjacent the heating vat 10 is float valve Water tank 14 through which the ,Water supply line 15 travels until it enters the bottom of the heating vat 10 in which the water is gradually heated until it reaches the outlet line 16 near the top of the vat 10. The heated water then passes by means of pipe line 16 through the chemical solution tank 17 by means of a heat exchanger 18 which is shown as a straight pipe in the drawing but may be made in any form to give the desired heating effect to the chemical solution. When the heat transfer occurs between heat exchanger 18 and the solution in tank 17, convection currents are established in the solution, causing a gentle yet efiective means for keeping the chemicals, which are usually supplied in powder form, suspended in solution.

The hot water upon leaving the heat exchanger 18 is directed by means of pipe line 19 into tank 14 in which it mixes with the chemical solution that is metered into tank 14 by means of the solution metering valve 20 in any desired ratio. The water level is maintained in tank 14 by means of float 21 which operates float valve 22 in supply line 15.

In the present instance, the vat 10 is shown mounted on a hollow base 23 which is also used as a chamber for supplying air under forced draft, to the burner 24 by means of fan 24 through opening 25. It will be noted that as hot water is forced into tank 14, a second agitation of hot water and preheated chemical solution occurs and causes hot water vapors to arise which, when introduced to the burner 24 as it is operating, creates a type of oxyhdrogen flame which will eliminate the heavy formation of soot and other carbon deposits on the steam coils 26 and inner wall 11 thereby increasing the overall efficiency of the device, especially resulting in a hotter flame, and lessening fuel costs considerably.

The preheated mixture of water and chemical solution in tank 14 is directed by means of, pipe line 27 to pumps 28, 28 and 28" which, by means of a plurality of check valves 29, as shown in Fig. 1, direct the preheated mixture under pressure by means of pipe line 30 to the steam coils 26 in which a saturated steam vapor suitable for steam cleaning is generated and directed by means of outlet-pipe line 31 to a flexible hose 32 and nozzle 33 out into the air or against an object to be cleaned, de-greased, sterilized or disinfected, etc.

It will be noted that a pressure gauge 34 and a pressure cut-off switch 35 are connected to outlet 31 thereby utilizing operating pressure for the indication on the gauge 34 and the operation of the cut off switch 35 which at a predetermined pressure will stop the operation of the fan 24 and the electric motor 36 which drives the pumps 28, 28', 28 and fuel pump 37 by means of connecting rods 38, 38', 38" and 38", respectively, thereby preventing any further build-up of pressure in the system until the excess pressure has been utilized by the operator, and also by stopping motor 36 the fuel which is pumped from fuel tank 39 through a plurality of check valves 40 to burner 24 by means of fuelline 41 is cut off thereby turning off the burner 24 which will'be automatically relighted when the pressure drops to a predetermined value by'means of electric spark plug '42,

and in this manner maintaining the operation of the device within certain 'pre-determined limits.

The machine is operated as follows: first, a water supply is connected to the water inlet 15 on the machine and the water supply turned on. connection is made to an outlet supplying the proper electric current and thehand switch 43 is closed tosupply current to fan 24', ignition coil 44, spark plug 42 and electric motor 36'which drives pumps 28, 28', 28 and fuel pump 37. The spark plug 42 will ignite the fuel at the burner 24 as soon'as pump 37"supplies fuel under pressure. After the pumps have run'long enough for a steady'stream of steam and water to issue from nozzle33, fuel valve -45 is opened to meter fuel to the burner in desired quantity. Solution valve '20 is then opened to meter-inthe desired quantity of chemical solution. Differen't jobs require varying strengths of solution. Since the solution is entirely cut off when the metering valve .20

is closed, only steam and hot water maybe pumped through the system,'thuspermitting the work to beflushed off with clear hot water or steam vapor.

If it is desired to de-grease and clean a-certain piece ofmachinery and it has been decided that the best agent for this work would be a mixture of steam'vaporand a detergent solution, the. above mentioned procedure should be followed and a full force of steam should beapplied to the work in order to knock off hardened deposits of grease and dirt. Next, a rich mixture of steam and detergent solution should be applied, followed by a gradual decrease of the detergent solution, by manipu- Next, the electrical 4 lating solution metering valve 20 and finally rinsing the machinery with clear steam vapor or hot Water.

By manipulating fuel metering valve 45, any desired pressure may be obtained and maintained within a range of nop. s. i. to the maximum capacity p. s. i. of the machine. It will be obvious that any capacity unit may be manufactured Without departing from the present invention.

The example given is typical of a common cleaning or tie-greasing operation. Other operations may also be performed with the same effectiveness and ease as the above mentioned, such as spraying insecticides, disinfectants, water soluble paints, including mill white and Whitewash, etc. In fact, in any operation where instantaneous steam vapor is desired, the use of the above described unit is of great advantage.

It should be remembered that both the main reservoir 13 and the supply tank 14 are not intended to be of the pressurized type as found in prior art; and, due to the above, cannot explode. This, coupled with the pressure cut-off switch 35 which will stop any build-up of pressure beyond a predetermined setting, make this machine extremely safe to operate.

While I have disclosed only the hot water from the water vat as a means to heat the water lines and tank, solution lines and tank, and pumping units, it is obvious that heat can be applied in other ways such as by the use of electrical or chemical heating elements to accomplish this purpose and to preventing freezing especially if the machine is to be left inoperative for any length of time in freezing temperature. So long as the machine is operating and generating steam or hot water, the unit described is not subject to freezing hazards.

While the accompanying drawings indicate the water float tank 14 is made integral with the hollow base 23, it will be obvious that said tank may be made to slide into the hollow base for the purpose of easily removing same for cleaning, repair, or replacement, without departing from the present invention. a

From the above description of operations, it is readily apparent that my machine is versatile, compact, and can be operated expertly by a novice.

Any combination of pressures and mixtures is possible to suit a given work to be performed. The detergents or other chemicals will readily mix with the steam or Water since they enter the supply tank 14 in a preheated state.

It will be obvious that my invention provides needed apparatus of great convenience and usefulness, and that while I have shown and described my invention in a very practical embodiment thereof, various changes and adaptations may be made without departing from the scope of my invention as defined in the appended claims.

I claim:

1. In a system of the class described, a reservoir, a burner in heat exchange relation with said reservoir, a float valve tank in vapor exchange relation with said burner, a supply pipe line passing through said float valve tank for supplying Water to said reservoir, a solution tank connected to supply solution to said float valve tank,pipe means in heat exchange relation with said solution tank and connecting said reservoir to said float valve tank for the passage of water from said reservoir to said float valve tank, a float valve in said supply pipe line responsive to the level of liquid in said float valve tank to control the level of'liquid therein, a heating coil in heat exchange relation with said burner, fluid pumping means connected to pump fluid from said float valve tank to said heating coil, and a flexible hose connected to said heating coil and provided with a nozzle for dispensing fluid from said heating coil.

2. In a system of the class de'scribe'd,'a closed reservoir, a burner in heat exchange relation with said reservoir, a float valve tank in vapor exchange relation with said burner, a supply pipe line passing through said float valve tank for supplying water to said reservoir, a solution tank connected to supply solution to said float valve tank, pipe means in heat exchange relation with said solution tank and connecting said reservoir to said float valve tank for the passage of water from said reservoir to said float valve tank, a float valve in said supply pipe line responsive to the level of liquid in said float valve tank to control the level of liquid therein, a heating coil wherein the confines of said reservoir and in heat exchange relation with said burner, fluid pumping means connected to pump fluid from said float valve tank to said heating coil, and a flexible hose connected to said heating coil and provided with a nozzle for dispensing fluid from said heating coil.

3. In a system of the class described, a closed reservoir. a burner in heat exchange relation with said reservoir, a float valve tank in heat and vapor exchange relation with said burner, a supply pipe line passing through said float valve tank for supplying Water to said reservoir, a solution tank connected to supply solution to said float valve tank, pipe means in heat exchange relation with said solution tank and connecting said reservoir to said float valve tank for the passage of water from said reservoir to said float valve tank, a float valve in said supply pipe line responsive to the level of liquid in said float valve tank to control the level of liquid therein, a heating coil within the confines of said reservoir and in heat exchange relation with said burner, a multiplicity of pumping units, certain of said pumping units being connected to pump liquid from said float valve tank to said heating coil and certain of said pumping units being connected to pump liquid from said float valve tank to the outlet of said heating coil at point Where a flexible hose may be attached for dispensing fluid.

4. In a system of the class described, a closed reservoir, a burner in heat exchange relation with said reservoir, a portable or removable float valve tank in heat and vapor exchange relation with said burner, a supply pipe line passing through said float valve tank for supplying water to said reservoir, a solution tank connected to supply solution to said float valve tank, pipe means for the passage of Water from said reservoir to said float valve tank, a float valve in said supply pipe line responsive to the level of liquid in said float valve tank to control the level of liquid therein, a heating coil Within the confines of said reservoir and in heat exchange relation With said burner, pumping unit connected to pump liquid from said float valve tank to the inlet side of said heating coil, and a pumping unit connected to pump liquid from said float valve tank to the outlet side of said heating coil References Qited in the file of this patent UNITED STATES PATENTS 1,568,789 Williarns Jan. 5, 1926 2,128,263 Ofeldt Aug, 30, 1938 2,289,674 Ofeldt July 14, 1942 2,487,348 Malsbary Nov. 8. 1949 2,605,137 Ofeldt July 29, 1952 2638.383 Hall May 12, 1953 

1. IN A SYSTEM OF THE CLASS DESCRIBED, A RESERVOIR, A BURNER IN HEAT EXCHANGE RELATION WITH SAID RESERVOIR, A FLOAT VALVE TANK IN VAPOR EXCHANGE RELATION WITH SAID BURNER, A SUPPLY PIPE LINE PASSING THROUGH SAID FLOAT VALVE TANK FOR SUPPLYING WATER TO SAID RESERVOIR, A SOLUTION TANK CONNECTED TO SUPPLY SOLUTION TO SAID FLOAT VALVE TANK, PIPE MEANS IN HEAT EXCHANGE RELATION WITH SAID SOLUTION TANK AND CONNECTING SAID RESERVOIR TO SAID FLOAT VALVE TANK FOR THE PASSAGE OF WATER FROM SAID RESERVOIR TO SAID FLOAT VALVE TANK, A FLOAT VALVE IN SAID SUPPLY PIPE LINE RESPONSIVE TO THE LEVEL OF LIQUID IN SAID FLOAT VALVE TANK TO CONTROL THE LEVEL OF LIQUID THEREIN, A HEATING COIL IN HEAT EXCHANGE RELATION WITH SAID BURNER, FLUID PUMPING MEANS CONNECTED TO PUMP FLUID FROM SAID FLOAT VALVE TANK TO SAID HEATING COIL, AND A FLEXIBLE HOSE CONNECTED TO SAID HEATING COIL AND PROVIDED WITH A NOZZLE FOR DISPENSING FLUID FROM SAID HEATING COIL. 